The present invention relates to a vehicle having a tandem or dual steering system, and, more particularly, to a tricycle or bicycle that can be steered from both a main steering assembly and a remote steering assembly.
There are, of course, various reasons for the use of a dual steering function on a vehicle such as a bicycle or a tricycle. In the case of a bicycle, such as a tandem bicycle or other bicycle where two riders are actually riding on the vehicle, it is advantageous to have a steering capability of both riders so that either can take over and command the steering function.
In the case of a tricycle, there is an advantage in that the young child learning to ride the tricycle can exercise control of the steering function but with a secondary or remote steering mechanism that can be accessible to an adult following behind to take over that steering function if the young child is steering in an erratic manner and needs guidance in the direction of the tricycle to avoid hitting an object or losing control of the vehicle.
Accordingly, certain remote steering devices have been proposed and in general such devices have been limited to use with either a bicycle or a tricycle. For example, in U.S. Pat. Nos. 5,924,713 and 6,120,048, both of Li, there is a auxiliary steering device adapted for use with a tricycle and the steering mechanism utilizes a pair of rods that communicate the steering function from a remote site to the main steering site. A difficulty in the LI systems, however, is in the use of solid rods that can be bent if overstressed and also the mechanism and its components are fairly open to the exterior environment and therefore unprotected. Thus there is a danger that a person or a person""s clothing can become entangled with the components of the mechanism.
In addition, the prior mechanisms for carrying out a remote steering function, including the Li systems, are generally limited in their ability to radially rotate the steered wheel, that is, there is only a limited amount that the main steering assembly and the remote steering assembly can be rotated in maneuvering the vehicle.
It would be advantageous to have a system that provides a linkage between the main steering assembly and a remote steering assembly that can be used on both a bicycle or a tricycle, has the ability to allow unlimited rotation of the steered wheel, is protective of the components of the respective assemblies and has a substantially flexible coupling between the main steering assembly and the remote steering assembly.
Accordingly, the present invention relates to a vehicle having a dual steering system that can be used with either a tricycle or a bicycle. In the invention the vehicle includes a frame having both a front steering sleeve and a rear steering sleeve with a transverse support arm that extends between the front steering sleeve and the rear steering sleeve.
A front shaft and a rear shaft are rotatably mounted within, respectively, the front steering sleeve and the rear steering sleeve. At the upper end of each of the front shaft and the rear shaft are steering devices that can be grasped by a user to rotate the front and rear shafts. Preferably, the front and the rear shafts are mounted so as to be parallel to each other.
The front shaft extends downwardly from the front steering sleeve and a front or steered wheel is rotatably affixed to the lower end of the front shaft so that the steered wheel can be turned as the front steering device and front shaft are turned to steer the vehicle. At least one rear wheel is also rotatably mounted to the frame, that is, if the vehicle is a bicycle, there is one rear wheel and if the vehicle is a tricycle, there are two rear wheels.
There is a coupling that connects the front and rear shafts so the both shafts turn together in tandem. Preferably, the coupling is a substantially flexible chain that is operatively connected to sprockets that are located on both of the front and rear shafts so that the coupling of the shafts is positive. Accordingly, rotating either the front steering device or the rear steering device will rotate both the front and rear shafts and, since the front wheel or steered wheel is affixed to the lower end of the front shaft, the movement of either the front or rear shafts will effectively steer the vehicle.
With the above dual steering system, the same steering system can be used with either a bicycle or a tricycle with equal applicability. In the preferred embodiment, the substantially flexible coupling is fully enclosed within the transverse support arm so that the coupling mechanism is protected and cannot catch on the users clothing or cause harm to the user during its operation. In addition, with the present invention, there is no rotational limit on the amount of turning of the steered front wheel and it can actually be rotated 360 degrees if desired, thus the ability to fully steer the vehicle is not constrained by any turning limits.
These and other features and advantages of the present invention will become more readily apparent during the following detailed description taken in conjunction with the drawings herein.